Dental apparatus.



R. W. GREENBERG.

DENTA APHRATUS.

Armenian msn mLzz. ma.

Patented Dec. 10, [918.

ulll.

UNiTED 1 sTATEsmi-:iATENT oFFIoE.

ynlitCBER'l-l W'fGBEENBEBaG. OF NEW-YORR .'N'Y, i

,i p eoiuatien-o: Letters Patent... Pgtnhzd Dem-10,1918;

Application sied 'Januarv'za isis. semi nu. ziarzdff 10 al1/whom er may concern/.f

Be it known that, I, Rnirr W. GREEN- iinmn n citizen of the United States, residingvr at New York,v in the county and State of New AYork, liave invented -new and useful Improvements Dental A 1 paratus, of which the following is afspeei cation.

This invention f relates` to dental instru' ments or' deviees particularly 4:adapted for obtaining `metal dies of* teeth for making gold and like crowns.

Among the objects of my `invention is to improve the construction of instruments o'r completed niay be fraotured 0rsevered into two substantially equal parts without tlie necessityof removing the mold from tlie device for that purpose. Other and further objects of niv invention will appear from" ieg thev following specification.

'The invention consists `further inthe matters hereinafter described and more particularly pointed out iii the nl ipeiided claims.

In the accompanying drawingsl Figure lfis'aftop plan view of 'a device constructed iii :wcm-dance withA my inventioii;

Fig. l is n vertiriil sec-tional View, ii'itl'i parts iii eleiziioii, iakeii on line PF- of Fig. l;

Fig. '.i transverse Sectional view taken on line 8-3 of Fig. 2; and

Fig. 4 is a top plan view of the mold after being fractured or severed into two substantially equal parts by the use of iny devie'e.

A dental instrument or apparatus einv bodying the features of my invention con prises, as illustrated in the drawings, a pair of relatively flat jaws or blades 10 and 11,

pivotally connected together at one end so that the same when grasped by the hland of the operator may 4be drawn one toward the other for severing or splitting a plaster of Paris or like dental niold intosubstantially two ual halfiportions or parts. One'of said b ades 'or jaws, preferably the one 11, ismade substantially L-sliaped, with the leg portion thereof extending lengthwise of the part onbse portion -ll f 11.v In order'to preve device andfootj portion 11"thereof'ext/ena'-YA 111g across 5,1101 @015mm 'of 1 the deviee endbe-4 ;lirer end.. mitn id ly connected, y' svenire. 11111112, 65 with the edlae'en Qr amr-'eiqefftlie-cfdssi are Asecured Y wfmhlsfb r ers 18, 18. E! tending trensverselysi:4 the handles 16,1211? "are screws 19; 20, ltliere being one in eeehfhendle end havin :screws: threaded or other ndwise :adjusba leieonsijm nefrti'on therewith, so that said sorewsinay bev-90 moved or turned endwise toward andfroinz! each other. As illustrated, said 'screws-'19,?- "ZQ :ire arranfred in alinement, `extiendfat right-angles through 'the handles, .anderey 11 threaded through the same just 4beyond tliew places of attachment of thehjendles with theflilades 10, 11. By this arrangement the inf-,- ner ends of the screws 19, 20 are silbstan--i tially opposite ec'h ethernEacheisere-i1,.sistA provided at its outer end withl nl thumb-:` 100 piece or enlarged head port-ion 21, 22, whichinay' be gras )ed in turning the screws. T'The. inner end o one screw, preerablylie' en'e 19, is pointed, while the inner el'idr ofthe-v` otlier serew 20 is provided withfanxaerhi-f 105 shaped bearing block 23, the latter'havilgf. swiveled or rotatable eonneetioni-'witli-ilid screw 20 so that said block may: prepellykA engage or bear against the model-carrying 5;1' member or stern 24, to Abe presently scribed. The remaining part of my shape of an open ended tube or sleeve, which may be made of rubber or any other desired material. Said flask 25 has a length substantially equal to the length of the blades 10, 11, as shown in Fig. 2, and, as illustrated, is tubular or cylindric in shape.

The instrument or apparatus described and shown is used in the following manner: The member or Stem 24 is made tapered in shape, so as to permit its being readily inserted into the material of which the dental mold is made. At the inner or smaller end of the member 24 is afiixed a model 2G of a tooth, the latter being obtained in the usual manner and of the usual form for making a die for a gold or like crown. The .flask 25 is then rested on one of its ends on a suitable base or table 27,50 as to close the now lower end of said flask. The fiask 25 is then filled, to a point short of its now open upper end, with plaster or investment material 28, the latter being in a fiuid or like state. Shortly after or before this has been done, the meinber 24 with its model 2G Vis inserted between the blades or jaws 10, 11 with the model 26 extending downward toward the cross-piece 11a of the blade 11, and the member 24 fixed or held in such position between the blades by the screws 19, 20, the latter being turned in the proper directions so as tofiorce their inner ends against the orton'iof the member 2-1 interposed there tween. The member 24 is so positioned and held by the screws that one-half of the same extends on each side of said screws. The blades 10, 11 and the interposed member and model are then oiled or greased so as to prevent such parts from adhering to the molding material 28, whereupon the parts are pressed downward into the molding material in the flask 25 while the molding material is in a soft or Huid condition. The lower end of the model 26 is held suiiiciently above thc cross or base part of the blade 11 so as to be completely enveloped in the moldin materialwhen my apparatus is pressed or orced into the same. The parts are pressed downward into the molding material to the proper extent, preferably until the cross bar cornes into contact with the' base' or table 27, but to limit the distance the blades and model are pressed downward, said blades are provided adjacent the handles with outwardly projecting lugs 29, 29 adapted to contact against the upper edge or rim of the fiask 25 and act as stop-members for the parts. The width across the two blades is substantially equal to the inner cross-sectional dimension of the flask 25, so that the blades and member 24 may be readily and easily forced downward into the iiask. The latter is preferably made c lindrical, so that no matter at what point tile blades are forced into the flask said 'blades will be diametrically arranged in the ask and always be in a position to sever or split the mold formed in the flask into two equal half portions or parts. After the plaster or molding material 28 has set, the entire apparatus is raised from the table and the flask 25 ulled endwise ofi' of the mold 28. ()ne of the screws, preferably the one 19, is then loosened, and the handles grasped by the operator and moved toward each other, as shown in dotted lines in Fig. 2. The inner edges of the blades being sharp or knifelike, the'inold 28, in the drawing of the blades together, is fractured or split through the mold cavity formed by the stem 24 and model tooth 26, into almost equal half portions or parts in a plane of the blades, asindicated b the dotted lines 30, 30 in Fig. 3 and as ilustrated in full lines in Fig. 4. When this has been accomplishedptheblades and model 26 are removed from the.V fractured mold. Then the twoparts 31, 31 of the latter are placed together with the mold cavity 32 therebetween and bound together by wire, or the fiask 25 may be used for such purpose. The mold 28may then be dried and the metal for making the crown be poured into the mold cavity 32, but drying of the mold may be dispensed with in case a metal of a low fusing point is used. The product produced by pouring the metal in the mold cavity 32 is of course the dental crown or part desired.

By the use of my device as described and shown, the making of dental crowns or the like is not only greatly facilitated and rendered luore accurate nml eliicient, but with my device it is possible to produce an accu rate mold and sever or split the saine eiiiciently and accurately into two half portions, desired in this character of work. 1t is to be noted that the blades extend on opposite sides of the mold 28 and also are embedded or project inward into the same and thus sever the mold to ythat extent before the blades are drawn together. Other and further advantages arising out of the use of my device will be readily apparent to those skilled in the art tu which my invention relates.

Although I have shown and described herein in detail one preferred form of device or apparatus embodying the features of my invention, yet it is to be of course understood that the details of construction and arrangement of parts shown may be variously changed and` modified without departing from the spirit and scope of my invention, and I do not wish to be limited to the exact details of construction and arrangement of parts illustrated except as pointed out in the appended claims.

I claim as my invention:

1. A device of the character described, comprising a pair of pivotally connected blades arranged to receive therebetween a plaster or like dental mold for splitting the ion same into two parts upon the drawing of one of `said blades toward the other, and said blades bein provided with means for holding a denta model therebetween.

2. A device of the character described, comprising a pair of pivotally connected blades arranged to receive therebetween a y plaster or like dental mold for splitting the same into two parts upon the drawing of one of said blades toward the other, and said blades being provided with set-screws for holding a dental model therebetween.

3. A devi of the character described, com rising a pair of blades, one of said bladgs being rovided with a cross-bar, the other of said Iblades having ivotal connection with said cross-bar so t at said blades may be drawn one toward the other, and said blades being provided with means for holdingjtherebetween a dental model.

4. A device of the character described, comprising a pair of blades, one of said blades being provided with a cross-bar, the other of said blades having pivotal connection with said cross-bar so that said blades may be drawn one toward the other, and said blades being provided with endwise ad- 'ustable members for holding a dental model between said blades.

5. A device ofl the character described, comprising a pair of blades, one of said blades being provided with a cross-bar, the other of said blades having ivotal connec- 'tion with said cross-barso t at said blades ma be drawn one toward the other, and sai blades bein provided with set-screws for holding a ental model between said blades.

A device of `the character described, comprising a pair of blades, one of said blades being rovided with a cross-bar, the other of sald lades having ivotal connection with said cross-bar so t at said blades may be drawn one toward the other, said blades being provided with set-screws for holding a dental model between said blades,

one of said set-screws being provided with a bearing block adapted to engage the dental model.

T. A device of, the character described, comprising a pair dt blades, one of said blades being provided with a cross-bar, the otherl of said blades having pivotal connec tion with said cross-bar so that said blades may be drawn one toward the other, each blade being provided with a handle, and said handles being provided with endwise adjustable members adapted to hold a dental model between said blades.

8. device of the character described, comprising, a pair of blades, one of. said blades being provided with a cross-bar, the other of said blades having pivotal connection with said cross-bar so that said blades may be drawn one toward the other7 each blade being provided with a handle, and said handles' being provided with set-screws for holding a dental model between said blades.

t). A.dcvicc of the character described, comprising two connected blades having portions arranged opposite each other and vfadal'ited to receive therebetween a plaster or like dental mold, and said blades being provided with means for holding a dental model therebetween.

10. device of the character described, comprising two connected blades having portions arranged opposite each other and adapted to receive therebetween a plaster or like dental mold, and said blades being provided with set screws for holding a dental model therebetween. A

In testimony that I claim the foregoing as my invention I affix my signature, in the presence of two witnesses, this 31st day of December, A. D. 1917.

ROBERT W. GREENBERG.

lvitnesses:

Maven Fnaxkm., Isaac (inseriamo. 

